mysql-truncated incorrect DOUBLE value: ' Undefined '

mysql-truncated incorrect DOUBLE value: ' Undefined '

How did I meet this problem?

I want to query the statistics from multiple tables, and save them to the table of figures, and I need to execute the SQL statement of the following structure:

Insert INTO table1 Select (select COUNT (*) from T1 where ...) c1, select (SELECT COUNT (*) from T1 where ...) c1

Executes a Select (SELECT COUNT (*) from T1 where ...) c1, select (SELECT COUNT (*) from T1 where ...) c1 no problem

Together execution will appear truncated incorrect DOUBLE value: ' Undefined '

The reason was found because:

Child Statement Select COUNT (*) from T1 where ... In the Where condition, there is a where lat! = 0

In the T1 table, the LAT is saved in the varchar format, when the LAT has a double value, it will be error:truncated incorrect Double value: ' Undefined '

How to resolve:

change where lat! = 0 to where lat! = ' 0 '

For the reasons why the Select (select COUNT (*) from T1 where ...) is executed separately c1, select (SELECT COUNT (*) from T1 where ...) c1 without an error, I don't know why.

mysql-truncated incorrect DOUBLE value: ' Undefined '